Grover Sta-Tite open back scalloped button tuners for vintage archtops, acoustics, etc.
These are excellent quality replacements for newer or vintage Martin and Gretsch guitars that use this style open back tuner.
These tuners are direct replacements that fit the existing hole and use the push in bushing.
The Grover part number is V97-18NA.
Bushings and screws included.